Aggregate formation under turbulence: small-scale biophysical interactions driving carbon flux in the ocean

湍流下的聚集体形成：驱动海洋碳通量的小规模生物物理相互作用

• 批准号: 1335088
• 负责人: Brian White
• 金额: $ 75万
• 依托单位: University of North Carolina at Chapel Hill
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-15 至 2019-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1335088&HistoricalAwards=false
• 关键词: Aggregate; formation; under; turbulence; small

The process of marine aggregate formation is extremely important to the global carbon cycle since sinking aggregates often dominate the carbon flux from the surface ocean, removing CO2 from active exchange with the atmosphere. Existing models predict that the rate of aggregate formation depends on both particle encounter and coagulation efficiency, but the specific relationships describing the latter's dependence on a range of measurable biological and physical factors are still lacking. In this study, researchers from the University of North Carolina at Chapel Hill will use an interdisciplinary approach to experimentally investigate how aggregate formation varies depending on three factors: 1) production of extracellular polymeric substances, 2) turbulence intensity, and 3) particle size. Results from this study will aid in our understanding of carbon export following phytoplankton blooms, and in predicting carbon cycling in a changing ocean.Broader Impacts: In collaboration with the University of North Carolina (UNC) Baccalaureate Education in Science and Teaching program, one undergraduate student training to become a high school teacher would participate in the study to obtain research experience. At the UNC Science Expo, the proponents plan a presentation to the general public on the importance of marine snow aggregates to global climate change. In addition, they plan a demonstration of their ongoing research project at the Joint Fluids Laboratory to the public, K-12 students, and government officials. One postdoc, one graduate student, and one undergraduate student would be supported and trained as part of this project.

海洋聚集体的形成过程对全球碳循环极为重要，因为下沉聚集体往往主导海洋表面的碳通量，从与大气的积极交换中去除CO2。现有的模型预测，聚集体形成的速度取决于颗粒相遇和凝聚效率，但描述后者的依赖于一系列可测量的生物和物理因素的具体关系仍然缺乏。在这项研究中，来自查佩尔山的北卡罗来纳州大学的研究人员将使用跨学科的方法来实验研究聚集体的形成如何取决于三个因素：1）细胞外聚合物的产生，2）湍流强度，3）颗粒大小。这项研究的结果将有助于我们理解浮游植物大量繁殖后的碳输出，并预测不断变化的海洋中的碳循环。更广泛的影响：与北卡罗来纳州大学（University of North Carolina）合作，一名接受高中教师培训的本科生将参加这项研究，以获得研究经验。 在海洋科学博览会上，支持者计划向公众介绍海洋雪对全球气候变化的重要性。 此外，他们计划在联合流体实验室向公众，K-12学生和政府官员展示他们正在进行的研究项目。 一名博士后，一名研究生和一名本科生将作为该项目的一部分得到支持和培训。